Notes on Using Epoxy Resins for High Power Rocketry

5 Minute Epoxy

A quick-cure epoxy is the workhorse of your HPR workshop. We can complete a step, and start the next step within the hour. This can keep up the pace for your project, especially when adding fillets to fins. 5 minute epoxy is commonly found “syringe-style” with equal parts being added for each with a push of the plunger. In fact, it is becoming somewhat difficult to find an epoxy that cures in longer than five minutes.

At One Way Rocketry, we have been very happy with JB Weld’s ClearWeld Professional Grade Epoxy, used in 90% of our cementing. It is also a very good value when compared to the little dual-syringe style systems.

The bottles are like little miniature ketchup and mustard bottles. You can cut the tip to almost as small or as large an opening as you would like, to adjust the flow. It is easy to restrict the flow and use only tiny amounts. Its also quite easy to open it up for a larger flow. Set time is five minutes, so stir fast and stir well and get busy, its only five minutes. Its rating of 3900 psi seems as strong as any clear epoxy we’ve found, despite the quick cure time. We think one can make one or two good High Power Rockets with this eight ounce total kit. The only thing its missing in this epoxy system is UV protection, so keep this epoxy below deck or under paint. Highly recommended epoxy.

Make sure to plan ahead when using 5 minute epoxy, or go ahead and use a slow cure epoxy. The longer it takes to cure, the stronger the bond, generally. Always keep “Extra Time” epoxy on hand so you don’t try to cheat time and get away with the 5 minute epoxy for everything.